Tissue severing devices with sliding support and methods

ABSTRACT

Tissue severing devices and methods are provided operable to be inserted through small surgical openings and advanced to tissue to be severed. The tissue severing device includes a cutting element that extends from a tube member during use. A slidable support ribbon is operable to support the cutting element at an angle to an axis of the tube member.

RELATED APPLICATIONS

This application is a continuation of and claims priority to U.S. patentapplication Ser. No. 13/495,023, now U.S. Pat. No. 8,585,727, which is acontinuation of and claimed priority to PCT patent application SerialNumber PCT/US10/24210, filed Feb. 14, 2010, entitled TISSUE SEVERINGDEVICES AND METHODS, incorporated herein in its entirety by reference.

FIELD

The present invention is related generally to the field of medicaldevices. More particularly, the present invention involves devices andmethods that enable accurate dissection of tissue such as associatedwith a patient undergoing surgery.

BACKGROUND

During surgical procedures and, more particularly, tissue removalprocedures, it is desirable to limit the size of the entry incision tominimize the trauma experienced by the patient. In the past, efforts tominimize entry incision size have generally been limited due to the sizeof the tissue to be removed and the need for access to the tissue.

However, in modern surgery access to the tissue cite is provided byinserting one or more trocar and cannula. Thereafter, one or morelaparoscopes are used to view the tissue to be removed, and additionalport sites are used to gain access to the tissue to sever it from tissuewhich is to remain. However, the entry incision must still be sized toallow removal of the severed tissue and, therefore, the reduction inentry incision size is rather limited even in more modern or recentlydeveloped surgical procedures.

Morcellators are devices that morcellate or cut tissue into smallerpieces to allow for easier removal through small surgical access sites.Morcellators that require a pushing or downward traction operation tocut the tissue present a danger of over extension into tissue that isnot to be injured. By way of example, but not limited thereto, in alaparoscopic subtotal hysterectomy, one way of minimizing the danger ofthis over extension is to amputate the body of the uterus from thecervix prior to morcellation. The amputation of the uterus presents anadded risk of injury to other organs, such as the rectum and bowel, asthey lie behind the uterus and are difficult to see during uterusamputation. Also, amputation is commonly performed using electrocauteryor harmonic scalpel which may cause lateral spread of heat or otherenergy and can inadvertently cause a burn to the bowel or bladder thatmay not be realized until days after surgery. Further, amputation of theuterus requires the use of one surgical instrument to amputate theuterus and another surgical instrument to morcellate the uterus withtheir associated cost and complexity of use.

Some known laparoscopic supracervical hysterectomy instruments utilizegraspers that pull tissue into a spinning tubular blade or the spinningblade is pushed into the tissue. These types of instruments have theirlimitations and dangers associated with their use, such as, but notlimited to, the exposed sharp blade possibly injuring surrounding tissuenot intended to be morcellated, discharge of the tissue in a spinningtool, and the difficulty and dangers of placing downward traction intothe target tissue.

There exists a need in the art for surgical devices and methods thatallow for more effective tissue severing and morcellating and whichallow for morcellation without the need to first amputate the tissue.

SUMMARY

In accordance with an embodiment, a tissue severing device comprises ahandle, a tube member, and inner member, and a cutting element. The tubemember includes an elongated tube having a tube member proximal endextending into the handle and a tube member distal end opposite the tubemember proximal end. The tube member defines a tube member lumen thatextends through the tube member proximal end to the tube member distalend and defining a tube member axis. The inner member includes anelongated body having an inner member proximal end extending through thetube member lumen and into the handle and an inner member distal endopposite the inner member proximal end. The inner member is operable tobe received within the tube member lumen. The cutting element includes acutting element proximal end and a cutting element distal end oppositethe cutting element proximal end. The cutting element proximal endextends into the inner member distal end. The cutting element distal endextends from the inner member distal end. The tube member distal end isoperable to move distally over and receive the inner member distal endand the inner member distal end therein. The tube member distal end isoperable to move in a proximal direction to expose the cutting elementdistal end.

In accordance with another embodiment, the handle further comprises anengagement means in operable engagement with the tube member proximalend operable to permit the tube member to be moved proximally anddistally over the inner member.

In accordance with another embodiment, the tissue severing device isoperable to present the cutting element distal end at an angle to thetube member axis when the tube member distal end is withdrawn from thecutting element distal end and at least a portion of the inner memberdistal end.

In accordance with another embodiment, at least a portion of the innermember distal end is biased to form a curve of a predetermined anglewith respect to the tube member axis when the tube member distal end iswithdrawn from at least a portion of the inner member distal end, and iselastically deformable operable to extend under the urging engagement ofthe tube member distal end when advanced over the inner member distalend.

In accordance with another embodiment, the tissue severing devicefurther comprises a supporting means operable to support the innermember distal end in a curved position when the inner member distal endis at least partially exposed by the withdrawal of the tube memberdistal end.

In accordance with another embodiment, the supporting means comprises afixed support ribbon. The fixed support ribbon comprises an elongatedbody including a fixed support ribbon proximal end and a fixed supportribbon distal end opposite the fixed support ribbon proximal end. Thefixed support ribbon proximal end is coupled to the tube member distalend within the tube member lumen and the fixed support ribbon distal endis coupled to the inner member distal end. The tube member distal end isoperable to advance over and receive the inner member distal end, thecutting element distal end, and the fixed support ribbon. The fixedsupport ribbon has a length that is operable to pull the inner memberdistal end into a curve with respect to the tube member axis when thetube member distal end is moved in a proximal direction and tosubstantially retain that curve when tissue is severed by the cuttingelement distal end.

In accordance with another embodiment, the inner member distal end isbiased to a substantially straight orientation along the tube memberaxis. The fixed support ribbon is operable to provide a pulling forcenecessary to flex the inner member distal end into a curve as well asprovide support to prevent the inner member distal end fromsignificantly extending toward the tube member axis when the cuttingelement distal end is pulled through tissue to be severed.

In accordance with another embodiment, the tissue severing devicefurther comprises a slidable support ribbon operable for supporting theinner member distal end in a curved position when the inner memberdistal end is at least partially exposed by the withdrawal of the tubemember distal end. The slidable support ribbon comprises an elongatedbody including a slidable support ribbon proximal end and a slidablesupport ribbon distal end opposite the slidable support ribbon proximalend. The slidable support ribbon proximal end extends through the tubemember lumen from about the tube member proximal end to about the tubemember distal end and adjacent the inner member. The slidable supportribbon distal end is positioned adjacent the inner member distal end andthe cutting element distal end.

In accordance with another embodiment, the tissue severing devicefurther comprises an engagement ring coupled to the inner member distalend. The slidable support ribbon distal end and the inner member distalend are slidingly coupled by cooperative engagement of the inner memberdistal end and the engagement ring. The slidable support ribbon distalend comprises a substantially uniform width body portion and a flaredportion at about the inner member distal end, wherein the flared portionhas a width that is larger than the body portion. The engagement ringcomprising a shape of a partial loop coupled to the inner member distalend transverse to an inner member axis. The engagement ring is operableto slidingly receive the body portion of the slidable support ribbondistal end and is undersized so as to not be able to receive the flaredportion therethrough. The flared portion is operable as a catch suchthat there is no further axial movement of the slidable support ribbondistal end relative to the engagement ring when the flared portionengages the engagement ring. The engagement of the flare portion withthe engagement ring is operable to provide a means for pulling the innermember distal end proximally and thus flex the inner member distal endto present the cutting element distal end to an angle to the tube memberaxis. The engagement ring is operable to be slidingly received withinthe tube member lumen.

In accordance with another embodiment, the cutting element comprises anelongated member that forms a contiguous element that defines a loop atthe cutting element distal end and two ends at the cutting elementproximal end.

In accordance with another embodiment, the cutting element distal endcomprises a substantially elastic material such that the cutting elementdistal end comprises a diameter somewhat larger than the inner diameterof the tube member lumen. When the tube member distal end is advanced inthe distal direction, the cutting element distal end substantiallyelastically deforms and is slidingly received within the tube memberlumen and when the tube member distal end is advanced in the proximaldirection, the cutting element distal end exits the tube member lumenand substantially elastically expands therefrom.

In accordance with another embodiment, the tissue severing devicefurther comprises an energy source coupled to the cutting element andoperable to assist the cutting element proximal end in cutting andsevering tissue.

In accordance with another embodiment, the energy source is housedwithin the handle. The inner member further comprises at least one innermember lumen extending through the inner member proximal end and theinner member distal end. The cutting element comprises an elongatedmember that forms a contiguous element that defines a loop at thecutting element distal end and two ends at the cutting element proximalend. The cutting element proximal end extends through the inner memberlumen to the handle and the two ends of the cutting element proximal endare coupled to the energy source.

In accordance with another embodiment, the tissue severing devicefurther comprises an engagement means operable for moving the tubemember proximally and distally over the inner member.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are illustrated by way of example and not by way oflimitation in the figures of the accompanying drawings, in which likereferences may indicate similar elements throughout the various figuresunless otherwise specified.

FIGS. 1A and 1B are perspective views of embodiments of tissue severingdevices comprising a handle, a tube member, an inner member, and acutting element;

FIG. 2A is a side view of the device distal end showing the cuttingelement distal end extending from the tube member distal end of anembodiment of the tissue severing device of FIG. 1A;

FIG. 2B is a side view of the device distal end showing the inner memberdistal end and the cutting element distal end extending from the tubemember distal end of an embodiment of the tissue severing device of FIG.1A;

FIG. 3 is a side cut-away view of the device distal end showing the tubemember distal end extending over and containing the inner member distalend and the cutting element distal end of an embodiment of the tissuesevering device of FIG. 1A;

FIGS. 4A-4C are side views of the device distal end showing aprogression of position of the inner member distal end in accordancewith embodiment;

FIGS. 5A and 5B are side cut-away views of the device distal end showingan embodiment of a supporting means comprising a fixed support ribbon ofan embodiment of the tissue severing device of FIG. 1B;

FIGS. 6A-6C are side views of the device distal end showing aprogression of positions of the inner member distal end, in accordancewith an embodiment;

FIG. 7A is a side, partial cut-away view of a tissue severing device 10in accordance with an embodiment;

FIGS. 7B-7C are perspective and top views, respectively, of the devicedistal end showing a slidable support ribbon as another embodiment of asupporting means operable for supporting the inner member distal end ina curved position when the inner member distal end is at least partiallyexposed by the withdrawal of the tube member distal end;

FIG. 7D is a perspective view of a device distal end comprising aslidable support ribbon and a plurality of engagement rings, inaccordance with another embodiment;

FIG. 8 is a cross-sectional view of the inner member distal end, aportion of the body portion of the slidable support ribbon distal end,and an engagement ring, in accordance with an embodiment;

FIGS. 9A-9D are side views of an embodiment of a mechanism forcontrolling the movement of the slidable support ribbon under theinfluence of the movement of the tube member;

FIGS. 10A and 10B are perspective and side views, respectively, of adistal end of another embodiment of a slidable support ribbon;

FIGS. 11A-11C are top, perspective, and top views, respectively, of thedevice distal end with the slidable support ribbon, in accordance withan embodiment;

FIG. 12 is a side view of a cutting element engagement elementcomprising a U-shaped flange, in accordance with an embodiment;

FIG. 13 is a side, partial cut-away view of an inner member, inaccordance with an embodiment;

FIG. 14 is a top view of the device distal end showing a bifurcatedinner member distal end, in accordance with the embodiment of FIG. 13;

FIG. 15 is a top, partial cut-away view of the device distal end showingthe inner member distal end, in accordance with another embodiment;

FIG. 16 is a side view of the device distal end showing a slidablesupport ribbon wherein the slidable support ribbon distal end is fixedlycoupled to the inner member distal end, in accordance with anembodiment;

FIG. 17 is a side cross-sectional view of an embodiment of a cuttingelement proximal end and an inner member distal end that are operablefor removable coupling engagement therebetween;

FIG. 18 is a partial cut-away view of an embodiment of a cutting elementand an inner member, in accordance with an embodiment;

FIG. 19A is a top view of an embodiment of a cutting element, inaccordance with an embodiment;

FIG. 19B is a perspective view of an embodiment of a cutting element, inaccordance with an embodiment;

FIGS. 19C and 19D are top views, expanded and compresses, respectively,of an embodiment of a cutting element, in accordance with an embodiment;

FIG. 19E is a top view showing an embodiment of a cutting element, inaccordance with an embodiment;

FIG. 19F is a top view showing another embodiment of a cutting element,in accordance with an embodiment;

FIG. 20 is a side partial cut-away view of the device distal end whereinthe cutting element distal end has a bias to an angle beta to the tubemember axis, in accordance with an embodiment;

FIG. 21 is a side cut-away view of a tissue severing device inaccordance with an embodiment;

FIG. 22 is a side view of the distal region of an embodiment of thetissue severing device as presented to tissue, in accordance with anembodiment;

FIG. 23 is a side view of the distal region of an embodiment of thetissue severing device as cutting through tissue, in accordance with anembodiment;

FIG. 24 is a side view of the distal region of an embodiment of thetissue severing device as presented to tissue, in accordance with anembodiment

FIG. 25 is a perspective view of a device distal end including an innermember distal end that is operable to allow for articulation, inaccordance with an embodiment; and

FIG. 26 is a perspective view of a device distal end including anotherinner member distal end that is operable to allow for articulation, inaccordance with an embodiment.

DETAILED DESCRIPTION

In the following description, embodiments of apparatus and methods willbe disclosed. For purposes of explanation, specific numbers, materials,and/or configurations are set forth in order to provide a thoroughunderstanding of the embodiments. However, it will also be apparent tothose skilled in the art that the embodiments may be practiced withoutone or more of the specific details, or with other approaches,materials, components, etc. In other instances, well-known structures,materials, and/or operations are not shown and/or described in detail toavoid obscuring the embodiments. Accordingly, in some instances,features are omitted and/or simplified in order to not obscure thedisclosed embodiments. Furthermore, it is understood that theembodiments shown in the figures are illustrative representations andare not necessarily drawn to scale.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of claimed subject matter. Thus, theappearances of the phrase “in one embodiment” or “an embodiment” invarious places throughout this specification are not necessarily allreferring to the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in one or moreembodiments.

Reference will now be made to embodiments illustrated in the drawingsand specific language which will be used to describe the same. It willnevertheless be understood that no limitation of the scope of theinvention is thereby intended. Alterations and further modifications ofthe illustrated embodiments and further applications of the principlesof the invention, as would normally occur to one skilled in the art towhich the invention relates, are also within the scope of the invention.

Tissue severing devices as provided in embodiments herein are operableto be inserted through small surgical openings, such as, but not limitedto, being inserted through a trocar sleeve at a laparoscopic port siteand advanced to tissue to be severed or morcellated. The tissue severingdevice is operable to directly sever or morcellate tissue within apatient's body.

FIGS. 1A and 1B are perspective views of tissue severing devices 10comprising a handle 50, a tube member 20, an inner member 30, and acutting element 40, in accordance with two embodiments. The tube member20 comprises an elongated relatively stiff tube having a tube memberproximal end 22 extending into the handle 50 and a tube member distalend 24 opposite the tube member proximal end 22. The tube member 20defines a tube member lumen 26 that extends through the tube memberproximal end 22 to the tube member distal end 24 defining a tube memberaxis X. The inner member 30 comprises an elongated body having an innermember proximal end 32 (hidden from view) extending through the tubemember lumen 26 and into the handle 50 and an inner member distal end 34opposite the inner member proximal end 32. The inner member 30 isoperable to be received within the tube member lumen 26.

The cutting element 40 comprises a cutting element proximal end 42(hidden from view) that enters the inner member distal end 34, shown inFIG. 18, and a cutting element distal end 44 opposite the cuttingelement proximal end 42. The cutting element distal end 44 extends fromthe inner member distal end 34.

The tissue severing device 10 includes a device proximal end 14 thatgenerally includes the handle 50 and a device distal end 16 thatgenerally includes the tube member distal end 24, the inner memberdistal end 34, and the cutting element distal end 44.

FIG. 2A is a side view of the device distal end 16 showing the cuttingelement distal end 44 extending from the tube member distal end 24. FIG.2B is a side view of the device distal end 16 showing the inner memberdistal end 34 and the cutting element distal end 44 extending from thetube member distal end 24. FIG. 3 is a side cut-away view of the devicedistal end 16 showing the tube member distal end 24 extending over andcontaining the inner member distal end 34 and the cutting element distalend 44. The tube member distal end 24 is operable to move in a distaldirection (away from the handle 50) over and with the tube lumen 26operable to receive the inner member distal end 34 and the cuttingelement distal end 44 therein, as shown in FIG. 3. The tube memberdistal end 24 is also operable to move in a proximal direction (towardthe handle 50) to expose the cutting element distal end 44, as shown inFIG. 2A, and, in other embodiments, also expose at least a portion ofthe inner member distal end 34, as shown in FIGS. 1A, 1B and 2B, so asto present the cutting element distal end 44 to tissue to be cut orsevered.

Referring again to FIGS. 1A and 1B, in accordance with an embodiment,the tube member proximal end 22 includes an engagement means incooperative engagement with the handle 50 operable to permit the tubemember 20 to be moved proximally and distally over the inner member 30.It is anticipated that there are many engagement means that may be usedto provide the function for permitting the movement of the tube member20 proximally and distally over the inner member 30, some of which aredescribed below.

The tube member 20 may comprise any suitable material, including, butnot limited to, stainless steel, plastic, PTFE, polymer, and compositematerials. In addition, the interior and/or exterior surfaces of theinner member 30 and tube member 20 may be coated with a low frictionmaterial such as, but not limited to, PTFE, Teflon®, polyvinylidenefluoride, polyethylene, or another polymeric material to facilitatemovement of the tube member 20 with respect to the inner member 30 andcutting element distal end 44.

In accordance with an embodiment, the tissue severing device 10 isoperable to present the cutting element distal end 44 extending from thetube member distal end 24 substantially parallel with the tube memberaxis X, as shown in FIG. 2A. The tube member distal end 24 is operableto move proximately such that the cutting element distal end 44 isexposed so as to be available for use to cut or sever tissue. Inaccordance with an embodiment, the inner member 30 may be relativelystiff so as to support the cutting element 40 from deflecting during useto cut or sever tissue.

In accordance with another embodiment, the tissue severing device 10 isoperable to present the cutting element distal end 44 at an angle alphato the tube member axis X when the tube member distal end 24 iswithdrawn from the cutting element distal end 44 and at least a portionof the inner member distal end 34, as shown in FIG. 2B. In accordancewith an embodiment, the inner member distal end 34 is operable to curveaway from and form an angle alpha with the tube member axis X when theinner member distal end 34 is exposed by the withdrawal of the tubemember distal end 24 therefrom. FIGS. 4A-4C are side views of the devicedistal end 16 showing a progression of position of the inner memberdistal end 34. As the tube member distal end 24 withdraws from the innermember distal end 34, the angle alpha becomes progressively larger to afinal predetermined angle alpha. In accordance with embodiments, thepredetermined angle alpha may be any angle to the tube member axis X. Inaccordance with an embodiment, the predetermined angle alpha may be upto and including 90 degrees to the tube member axis X.

The tube member distal end 22, by being moved proximally or distally,may be used, among other things, to control the angle alpha of thecutting element distal end 44 and the cutting depth into the tissue asthe tissue is being cut or severed.

In accordance with an embodiment, at least a portion of the inner memberdistal end 34 is biased to form a curve of a predetermined angle alphawhen the tube member distal end 24 is withdrawn from over the innermember distal end 34. The means for providing the bias that affects thecurve in the inner member distal end 34 may include one or a combinationof the elastic properties of the tube member distal end 24 and a supportmeans, as further described below.

In accordance with an embodiment, the at least a portion of the innermember distal end 34 that is elastically biased to form a curve of apredetermined angle alpha is elastically deformable so as to extend(straighten) under the urging engagement of the tube member distal end24 advancing distally over the inner member distal end 34. The innermember distal end 34 and the cutting element distal end 44 areoperatively stiff so as to prevent substantial extension or deflectionof either or both of the inner member distal end 34 and the cuttingelement distal end 44 toward the tube member axis X under the forcesencountered when the cutting element distal end 44 penetrates, cuts,and/or severs tissue, but not so stiff so as to prevent the extension ofthe inner member distal end 34 and the cutting element distal end 44under the force of the tube member distal end 24 moving distallythereover.

In accordance with embodiments, the at least a portion of the innermember distal end 34 comprises any suitable material or assembly so asto be elastically deformable as well as either biased to besubstantially straight or biased to form a curve of a predeterminedangle alpha. Suitable materials include, but are not limited to,heat-set and cold-formed stainless steel and alloys thereof,super-elastic shape memory alloys including nickel-titanium alloys,preferentially-braided tubing and sleeves, and heat set or cold formedpolymer and composite materials, among others, in forms such as, but notlimited to, wires, ribbons, rods, sleeves, and tubes.

It is appreciated that there may be many apparatus that may be utilizedto affect articulation of the inner member distal end 34. Such apparatusto affect articulation may include, but not limited to, one or morepivots, joints, extensible tubing, and rigid segments coupled byflexible or elastic interconnects. Embodiments representative ofexamples of such apparatus are provided in the discussion of FIGS. 25and 26.

It is understood that the inner member 30 and the tube member 20 maycomprise more than one material along the length of or at differentportions of the inner member 30 and tube member 20 suitable for aparticular purpose. By way of example, the inner member distal end 34may be elastically deformable wherein the inner member proximal end 32may be relatively stiffer as compared with the inner member distal end34.

In accordance with other embodiments, and as an alternative to relyingentirely on the elastic properties of the inner member distal end 34 toaffect the suitable balance of stiffness for the particular purpose asdescribed above, the tissue severing device 10 further comprises asupport means. As also provided below, the support means may be used tothe advantage of guiding tissue to be severed into the cutting elementdistal end 44 and controlling the depth of the cut, regardless of thesupport means' contribution to establishing the curve of the innermember distal end 34 or controlling extension of the inner member distalend 34 toward the tube member axis X while the cutting element distalend 44 is pulled through tissue to be severed.

In accordance with embodiments of the tissue severing device 10, thetissue severing device 10 further comprises supporting means forsupporting the inner member distal end 34 in a curved position when theinner member distal end 34 is at least partially exposed by thewithdrawal of the tube member distal end 24 therefrom. The supportingmeans may be used in combination with or in lieu of any bias to apredetermined curvature that may be present in the inner member distalend 34 as described above.

FIGS. 5A and 5B are side cut-away views of the device distal end 16showing an embodiment of a supporting means comprising a fixed supportribbon 60, also shown in the embodiment of FIG. 1B. The fixed supportribbon 60 comprises an elongated body including a fixed support ribbonproximal end 62 and a fixed support ribbon distal end 64 opposite thefixed support ribbon proximal end 62. The fixed support ribbon proximalend 62 is coupled to the tube member distal end 24 within the tubemember lumen 26 and the fixed support ribbon distal end 64 is coupled tothe inner member distal end 34.

The tube member distal end 24 is operable to advance over and receivethe inner member distal end 34, the cutting element distal end 44, andthe fixed support ribbon 60, as shown in FIG. 5A. The tube member distalend 34 may be moved in the proximal direction so as to withdraw from thecutting element distal end 44, the inner member distal end 34, and aportion of the fixed support ribbon 60, as shown in FIG. 5B. The fixedsupport ribbon 60 has a length that is operable to pull the inner memberdistal end 34 into a curve and to substantially retain that curve astissue is severed by the cutting element distal end 44.

FIGS. 6A-4C are side views of the device distal end 16 showing aprogression of positions of the inner member distal end 34. When thetube member distal end 24 covers the cutting element distal end 44, asshown in FIG. 6A, the fixed support ribbon 60 is generally slack anddoes not exhibit a significant force on the inner member distal end 34.As the tube member distal end 24 is moved proximally (toward the handleas shown in FIG. 1B), and moving the fixed support ribbon proximal end62 proximally, exposing at least a portion of the inner member distalend 34, the fixed support ribbon 60 becomes taught and begins to exert apulling force on the inner member distal end 34 which bends the innermember distal end 34 to an angle alpha to the tube member axis Xdependent on the distance that the tube member distal end 24 has movedproximally, as shown in FIGS. 6B and 6C.

As the tube member distal end 24 is moved distally to progressivelycover the inner member distal end 34, the fixed support ribbon proximalend 62 moves distally with the tube member distal end 24 allowing theinner member distal end 34 to extend toward the tube member axis X. Inan embodiment wherein the inner member distal end 34 has a curve bias,that is, is biased to a predetermined curve, the fixed support ribbon 60in combination with the tube member distal end 24 provides support toprevent the inner member distal end 34 from extending significantlytoward the tube member axis X when the cutting element distal end 44 ispulled through tissue to be severed which may present forces that mayovercome the curve bias of the inner member distal end 34 were it notfor the fixed support ribbon 60. In addition, or in the alternative, thefixed support ribbon 60 assists in controlling the depth of cut of thecutting element distal end 44 by impinging on and guiding the tissueinto the cutting element distal end 44, as will be discussed furtherbelow.

The fixed support ribbon 60 is operable to control the depth of cut intothe tissue by the cutting element distal end 44. During use, the fixedsupport ribbon 60 slides along the tissue edge substantially preventingthe cutting element distal end 44 from sinking into the tissue to adepth greater than the length of the cutting element distal end 44.

In an embodiment wherein the inner member distal end 34 has a straightbias, that is, is biased to a substantially straight orientation alongthe tube member axis X, the fixed support ribbon 60 in combination withthe tube member distal end 24 provides the pulling force necessary tobend the inner member distal end 34 into a curve as well as providesupport to prevent the inner member distal end 34 from significantlyextending toward the tube member axis X when the cutting element distalend 44 is pulled through tissue to be severed. Additionally, the fixedsupport ribbon 60 assists in controlling the depth of cut of the cuttingelement distal end 44 by guiding the tissue to be severed into thecutting element distal end 44, as will be discussed further below.

The tube member distal end 24, by being moved proximally or distally, incombination with the fixed support ribbon 60, may be used, among otherthings, to control the angle alpha of the cutting element distal end 44and the cutting depth into the tissue as the tissue is being cut orsevered.

FIG. 7A is a side, partial cut-away view of a tissue severing device 10and FIGS. 7B-7C are perspective and top views, respectively, of thedevice distal end 16 showing a slidable support ribbon 160 as anotherembodiment of a supporting means operable for supporting the innermember distal end 34 in a curved position when the inner member distalend 34 is at least partially exposed by the withdrawal of the tubemember distal end 24. The slidable support ribbon 160 may be used incombination with or in lieu of any bias to a predetermined curvaturethat may be present in the inner member distal end 34.

The slidable support ribbon 160 comprises an elongated body including aslidable support ribbon proximal end 162 and a slidable support ribbondistal end 164 opposite the slidable support ribbon proximal end 162.The slidable support ribbon proximal end 162 extends through the tubemember lumen 26 from about the tube member proximal end 22 to the tubemember distal end 24 and adjacent the inner member 30. The slidablesupport ribbon distal end 164 is positioned adjacent the inner memberdistal end 34 and the cutting element distal end 44 and is operablyengaged therewith as detailed below.

The slidable support ribbon proximal end 162 is positioned generallyadjacent the handle 50 and may be operably engaged by the user orelements of the tissue severing device 10 as detailed below.

In accordance with an embodiment, the slidable support ribbon distal end164 is operable to support the inner member distal end 34 into a curvedshape when the tube member distal end 24 is withdrawn therefrom. Theslidable support ribbon 160 is operable to substantially prevent theinner member distal end 34 from extending toward the tube member axis Xwhen the cutting element distal end 44 is pulled through tissue to besevered. The slidable support ribbon 160 is also operable to, amongother things, control the depth of cut into the tissue by guiding thetissue toward the cutting element distal end 44.

In another embodiment, the slidable support ribbon distal end 164 isalso operable to, among other things, protect the tube member lumen 26from being damaged by a sharp edge 45 of the cutting element distal end44 by acting as a barrier therebetween. In accordance with anembodiment, the slidable support ribbon distal end 164 comprises arelatively flat profile so as to cover at least a portion of the cuttingelement distal end 44 when the slidable support ribbon distal end 164 isextended there over. The slidable support ribbon distal end 164 isoperable to extend between a sharp edge 45, shown in FIG. 7C, of thecutting element distal end 44 and a portion of the tube member lumen 26when the tube member distal end 24 is extended over the cutting elementdistal end 44. The slidable support ribbon distal end 164 is operable towithdraw from adjacent the sharp edge 45 of the cutting element distalend 44 when the tube member distal end 24 is withdrawn from over thecutting element distal end 44.

In accordance with an embodiment, the slidable support ribbon distal end164 is operable to begin withdrawing proximally from being adjacent thecutting element distal end 44 as the cutting element distal end 44begins to be exposed by the withdrawing tube member distal end 24. Inthis embodiment, the slidable support ribbon distal end 164 is exposedsubstantially concurrently with the exposure of the inner member distalend 34 by the tube member distal end 24. In other words, the slidablesupport ribbon distal end 164 is not adjacent the portion of the cuttingelement distal end 44 that is exposed by the withdrawing tube memberdistal end 24 such that the cutting element distal end 44 may beginsevering tissue immediately upon withdrawal of the tube member distalend 24.

In accordance with another embodiment, the slidable support ribbondistal end 164 is operable to at least partially be adjacent the cuttingelement distal end 44 as the cutting element distal end 44 and theslidable support ribbon distal end 164 are exposed by the withdrawingtube member distal end 24. In this embodiment, the slidable supportribbon distal end 164 is withdrawn from adjacent the cutting elementdistal end 44 after the cutting element distal end 44 is at leastsubstantially exposed by the withdrawing tube member distal end 24. Theslidable support ribbon distal end 164 may come between at least aportion of the sharp edge 45 of the cutting element distal end 44 andadjacent tissue near which it is placed. The user may withdraw theslidable support ribbon distal end 164 into the tube member lumen 26 inwhich the cutting element distal end 44 may then sever tissue.

In another embodiment, as the tube member distal end 24 is furtherwithdrawn so as to expose a portion of the inner member distal end 34,the slidable support ribbon distal end 164 is withdrawn from adjacentthe cutting element distal end 44 and operably engages the inner memberdistal end 34 so as to provide at least one of the following functions,including, but not limited to, support the inner member distal end 34into an arc shape, to substantially prevent the inner member distal end34 from extending toward the tube member axis X while the cuttingelement distal end 44 is pulled through tissue to be severed, andcontrol the depth of cut into the tissue by guiding the tissue towardthe cutting element distal end 44.

The slidable support ribbon 160 is operable to control the depth of cutinto the tissue by the cutting element distal end 44. During use, theslidable support ribbon 160 slides along the tissue edge substantiallypreventing the cutting element distal end 44 from sinking into thetissue to a depth greater than the length of the cutting element distalend 44.

As discussed above, the slidable support ribbon distal end 164 and thetube member distal end 24 are operably engaged to provide the desiredfunctions. In accordance with the embodiments of FIGS. 7A-7C, theslidable support ribbon distal end 164 is slidingly coupled to the innermember distal end 34. As the inner member distal end 34 is exposed bythe withdrawing tube member distal end 24, the user may pull theslidable support ribbon proximal end 162 in the proximal direction so asto withdraw the slidable support ribbon proximal end 162 from adjacentthe cutting element distal end 44 and bend the inner member distal end34 into a desired arc to present the cutting element distal end 44 tothe tissue at an angle alpha to the tube member axis X. The user maycontrol the slidable support ribbon proximal end 162 in a desiredposition by pulling or pushing the slidable support ribbon proximal end162.

In accordance with an embodiment, the slidable support ribbon distal end164 and the inner member distal end 34 are slidingly coupled bycooperative engagement of the inner member distal end 34 and anengagement ring 168 coupled to the inner member distal end 34. Theslidable support ribbon distal end 164 comprises a substantially uniformwidth body portion 165 and a flared portion 167 at the slidable supportribbon distal end 164, wherein the flared portion 167 has a width thatis larger than the body portion 165.

The engagement ring 168 comprises a shape of a partial loop and iscoupled to the inner member distal end 34 transverse to an inner memberaxis X2. The engagement ring 168 is operable to slidingly receive thebody portion 165 of the slidable support ribbon distal end 164 but isundersized so as to not be able to receive the flared portion 167therethrough. The flared portion 167, thus, functions as a catch suchthat there is no further axial movement of the slidable support ribbondistal end 164 relative to the engagement ring 168 when the flaredportion 167 engages the engagement ring 168. Therefore, the engagementof the flare portion 167 with the engagement ring 168 provides a meansfor pulling the inner member distal end 34 proximally and thus flex theinner member distal end 34 into a desired arc to present the cuttingelement distal end 44 at an angle alpha to the tube member axis X.

FIG. 7D is a perspective view of the device distal end 16 comprising aslidable support ribbon 160 and a plurality of engagement rings 168 a,168 b in accordance with another embodiment. The plurality of engagementrings 168 a, 168 b are operable to support the slidable support ribbon160 in conformance with the curved position of the inner member distalend 34 when the inner member distal end 34 is at least partially exposedby the withdrawal of the tube member distal end 24.

The engagement ring 168 is operable to be slidingly received within thetube member lumen 26. FIG. 8 is a cross-sectional view of the innermember distal end 34, a portion of the body portion 165 of the slidablesupport ribbon distal end 164, and an embodiment of the engagement ring168. To assist in guiding the tube member distal end 24 over theengagement ring 168 so as to contain the engagement ring 168, theengagement ring 168 comprises a proximal edge 163 that is sloped facingproximally so as to guide the tube member distal end 24 over theengagement ring 168.

The engagement ring 168 is operable to slidingly receive the bodyportion 165 of the slidable support ribbon distal end 164. In accordancewith an embodiment, the engagement ring 168 comprises an inner surface161 that has a convex shape facing distally so as to assist in guidingthe body portion 165 of the slidable support ribbon distal end 164between the engagement ring 168 and the inner member distal end 34. Thismay be particularly advantageous when the slidable support ribbon distalend 164 is caused to flex at an angle so as to pull and/or support theinner member distal end 34 at an angle to the tube member axis X.

In accordance with an embodiment, the pullback of the slidable supportribbon 160 in the proximal direction so as to bend the inner memberdistal end 34 into a desired curve to present the cutting element distalend 44 at an angle alpha to the tube member axis X, and visa versa, maybe done in a manual operation by the user or an automatic operation bythe tissue cutting device 10. In accordance with an embodiment whereinthe slidable support ribbon 160 is manually controlled, the slidablesupport ribbon proximal end 162 is operable to be manipulated by theuser. In accordance with an embodiment, as shown in FIG. 7A, theslidable support ribbon proximal end 162 extends from the handle 50 suchthat the slidable support ribbon proximal end 162 may be grasped by theuser. The slidable support ribbon proximal end 162 and the handle 50 mayalso comprise an engagement element such that the slidable supportribbon proximal end 162 may be releasably coupled to the handle 50 whenthe slidable support ribbon 160 is extended or retracted to a desiredposition. The engagement element allows for temporarily fixating theposition of the slidable support ribbon proximal end 162.

It is anticipated that there are many suitable engagement elements thatprovide the function for releasably coupling the slidable support ribbonproximal end 162 to the handle 50. In an embodiment of an engagementelement, by way of example only and not limited thereto, as shown inFIG. 7A, a ratchet 150 may be operably engaged between the slidablesupport ribbon proximal end 162 and the handle 50. The ratchet 150allows for motion in the proximal direction while preventing motion inthe distal direction until controlled release. As is known in the art, aratchet 150 may comprise many devices, such as, but not limited to, apair of racks with intermeshing teeth, and a toothed gear and pawl.

It is appreciated that the movement of the slidable support ribbon 160may also be controlled by an electrical device, such as, but not limitedto, an electric motor. In accordance with an embodiment, the slidablesupport ribbon proximal end 162 is engaged with a motor that isautomatically or manually controlled operable to move the slidablesupport ribbon 160 proximally and distally.

In accordance with an embodiment wherein the slidable support ribbon 160is automatically controlled by the tissue severing device 10, theslidable support ribbon proximal end 162 is operable to be manipulatedby an interaction of elements of the tissue severing device 10.

In accordance with an embodiment wherein the slidable support ribbon 160is automatically controlled, the slidable support ribbon proximal end162 is cooperatively engaged with the tube member proximal end 22 suchthat when the tube member proximal end 22 is moved axially, the slidablesupport ribbon 160 may be moved axially as well. It is anticipated thatthere are many apparatus that may affect cooperation between theslidable support ribbon proximal end 162 and the tube member proximalend 22.

FIGS. 9A-9D are side views of an embodiment of a mechanism forcontrolling the movement of the slidable support ribbon 160 under theinfluence of the movement of the tube member 20. The slidable supportribbon proximal end 162 further comprises a snare 166 extending at anangle from the slidable support ribbon proximal end 162 operable tocatch a tube member proximal edge 21 of the tube member proximal end 22.

FIG. 9A shows a simplified view of the tube member 20 in the distalposition wherein the cutting element 40 is contained within the tubemember lumen 26. The snare 166 is spaced a predetermined distance fromthe tube member proximal edge 21. The predetermined distance may besubstantially the same as the length of the cutting element 40 such thatwhen the tube member distal end 24 has retracted from the cuttingelement distal end 44, the tube member proximal edge 21 may engage thesnare 166, as shown in FIG. 9B. As the tube member 20 is moved furtherin the proximal direction, the tube member proximal edge 21 engages thesnare 166 so as to pull the slidable support ribbon 160 in the proximaldirection and thus move the slidable support ribbon distal end 164 fromadjacent the cutting element distal end 44, as shown in FIG. 9C. As thetube member 20 is moved further in the proximal direction, the slidablesupport ribbon 160 is moved further in the proximal direction and thusthe slidable support ribbon distal end 164 engages the inner memberdistal end 34 so as to support the cutting element distal end 44 at anangle alpha to the tube member axis X. In accordance with an embodiment,the slidable support ribbon distal end 164 may be coupled to a biasingelement 265 such that the slidable support ribbon 160 is urged to movein the distal direction when the tube member 20 is moved in the distaldirection.

FIGS. 10A and 10B are perspective and side views, respectively, of adistal end 1164 of another embodiment of a slidable support ribbon 1160.The slidable support ribbon 1160 is an embodiment of a supporting meansthat is operable for supporting the inner member distal end 34 in acurved position when the inner member distal end 34 is at leastpartially exposed by the withdrawal of the tube member distal end 24 andoperable to support the cutting element distal end 44 in an openposition. The slidable support ribbon 1160 may be used in combinationwith or in lieu of any bias to a predetermined curvature, includingstraight, that may be present in the inner member distal end 34.

The slidable support ribbon 1160 comprises an elongated body including aslidable support ribbon proximal end 162, a slidable support ribbondistal end 1164 opposite the slidable support ribbon proximal end 162,and a ribbon body portion 1161 therebetween. The slidable support ribbondistal end 1164 comprises a cutting element engagement element 1170operable to engage the cutting element portions 144 a, 144 b of thecutting element distal end 44 about the inner member distal end 34 asshown in FIGS. 11B-11C and discussed below. In accordance with theembodiment of FIGS. 10A-10B, the cutting element engagement element 1170comprises a flange 1168 depending at about a 90 degree angle from theribbon body portion 1161. The flange 1168 is operable to be receivedwithin the loop formed by the cutting element distal end 44.

Substantially similar to the embodiment of the slidable support ribbon160 of FIG. 7A, the slidable support ribbon proximal end 162 of theslidable support ribbon 1160 extends through the tube member lumen 26from about the tube member proximal end 22 to the tube member distal end24 and adjacent the inner member 30. FIGS. 11A-11C are top, perspective,and top views, respectively, of the device distal end 16 with theslidable support ribbon 1160 in accordance with an embodiment. Theslidable support ribbon distal end 1164 is positioned adjacent the innermember distal end 34 and the cutting element distal end 44 and isoperably engaged therewith as detailed below.

As shown in FIG. 11A, when the cutting element distal end 44 ispositioned within the tube member distal end 24, the flange 1168 of theslidable support ribbon distal end 1164 is positioned within the loopformed by the cutting element distal end 44 and does not substantiallyengage the cutting element distal end 44. As shown in FIGS. 11B-11C,when the cutting element distal end 44 is exposed by the withdrawal ofthe tube member distal end 24, the slidable support ribbon 1160 may bemoved proximally such that the flange 1168 engages the cutting elementportions 144 a, 144 b of the cutting element distal end 44 assisting inspreading apart the cutting element portions 144 a, 144 b and thusassisting in opening and stabilizing the loop formed by the cuttingelement distal end 44. The flange 1168 helps to stabilize, or hold-open,the cutting element distal end 44 during subsequent tissue severing. Theflared portion 167 of the slidable support ribbon distal end 1164engages the engagement ring 168 reducing any further traction on thecutting element distal end 44 by the flange 1168.

The slidable support ribbon distal end 1164 is also operable to supportthe inner member distal end 34 into a curved shape at an angle alpha tothe tube member axis X when the tube member distal end 24 is withdrawntherefrom. The slidable support ribbon 1160 is operable to substantiallyprevent the inner member distal end 34 from extending toward the tubemember axis X when the cutting element distal end 44 is pulled throughtissue to be severed. The slidable support ribbon 1160 is also operableto, among other things, control the depth of cut into the tissue byguiding the tissue toward the cutting element distal end 44.

Substantially similar to the embodiment of FIG. 7A, the slidable supportribbon distal end 1164 is slidingly coupled to the inner member distalend 34 by an engagement ring 168. The slidable engagement of theslidable support ribbon 1160 of FIGS. 11A-11C is substantially the sameas the slidable engagement of the embodiments of FIGS. 7A-7C. Inaccordance with an embodiment, the slidable support ribbon distal end1164 is flared so as to engage the engagement ring 168 so as to positionthe cutting element distal end 44 as described above and shown in FIG.11B. The slidable support ribbon distal end 1164 is flared also so as toprovide a broader flange 1168 so as to more greatly engage and spreadapart the cutting element portions 144 a, 144 b of the cutting elementdistal end 44.

It is appreciated that the cutting element engagement element 1170 ofthe slidable support ribbon distal end 1164 that is operable to engagethe cutting element portions 144 a, 144 b of the cutting element distalend 44 may have a shape suitable for a particular purpose. FIG. 12 is aside view of a cutting element engagement element 1170 comprising aU-shaped flange 1169 operable to engage and substantially wrap aroundthe cutting element portions 144 a, 144 b of the cutting element distalend 44. The U-shaped flange 1169 is operable to contain a portion of thecutting element portions 144 a, 144 b therein so as to prevent thecutting element portions 144 a, 144 b from slipping from the engagementof the U-shaped flange 1169.

It is appreciated that direct contact of the cutting element engagementelement 1170 with the cutting element portions 144 a, 144 b may not besuitable for every purpose. By way of example, but not limited thereto,direct contact may reduce freedom of movement of the cutting elementdistal end 44 when energized by an energy source as discussed below. Byway of another example, but not limited thereto, direct contact maycause electrical conductivity issues when the cutting element distal end44 is energized by an electrical source such as in electrocautery. It isappreciated that there are many ways to prevent the direct contactbetween the cutting element engagement element 1170 and the cuttingelement portions 144 a, 144 b themselves when the cutting elementengagement element 1170 is moved proximally so as to assist in spreadingapart the cutting element portions 144 a, 144 b and thus opening ormaking more circular the loop formed by the cutting element distal end44.

FIG. 13 is a side, partial cut-away view of an inner member 30 furthercomprising two inner member lumens 36 a,b that are substantiallyparallel and that extend from the inner member proximal end 32 to theinner member distal end 34 therethrough, in accordance with anembodiment. The inner member distal end 34 further comprises a slit 135between the two inner member lumens 36 a,b, that extends from the innermember distal end 34 to a predetermined distance proximally operable toproduce a bifurcation of the inner member distal end 34 defining twobranch portions 234 a,b each containing one of the two inner memberlumens 36 a,b. The two inner member lumens 36 a,b are operable such thateach of the cutting element portions 144 a, 144 b of the cutting elementdistal end 44 may be received and extend into one of the two innermember lumens 36 a,b.

FIG. 14 is a top view of the device distal end 16 showing a bifurcatedinner member distal end 34 in accordance with the embodiment of FIG. 13.The inner member distal end 34 is bifurcated along the slit 135, thebifurcation being formed under the urging engagement of one or more ofthe spring bias of the cutting element 44 and the cutting elementengagement element 1170 of the slidable support ribbon distal end 1164.In the case of the cutting element engagement element 1170, the cuttingelement engagement element 1170 engages the two branch portions 234 a,bof the inner member distal end 34 about the cutting element portions 144a, 144 b of the cutting element distal end 44 effectively creatingand/or supporting the bifurcation of the inner member distal end 34. Thecutting element engagement element 1170 engages the two branch portions234 a,b as shown in FIG. 14 rather than the cutting element portions 144a, 144 b themselves as shown in FIG. 11B.

FIG. 15 is a top, partial cut-away view of the device distal end 16showing the inner member distal end 34, in accordance with anotherembodiment. The tissue severing device 10 further comprises two cuttingelement sleeves 230 a,b. Each cutting element sleeve 230 a,b comprisesan elongated body having a cutting element sleeve proximal end 232 a,bextending through the inner member lumen 36 and into the handle 50 and acutting element sleeve distal end 234 a,b opposite the cutting elementsleeve proximal end 232 a,b. Each of the two cutting element sleeves 230a,b further comprises a sleeve lumen 236 a,b that extends from thecutting element sleeve proximal end 232 a,b to the cutting elementsleeve distal end 234 a,b therethrough. The cutting element portions 144a, 144 b of the cutting element distal end 44 are operable to bereceived within the sleeve lumen 236 a,b.

The two cutting element sleeves 230 a,b spread apart from each otherunder the urging engagement of one or more of the spring bias of thecutting element 44 and the cutting element engagement element 1170 ofthe slidable support ribbon distal end 1164. In the case of the cuttingelement engagement element 1170, the cutting element engagement element1170 engages the two cutting element sleeve distal ends 234 a,b aboutthe cutting element portions 144 a, 144 b of the cutting element distalend 44 effectively assisting in spreading apart the cutting elementportions 144 a, 144 b and thus opening or making more circular the loopformed by the cutting element distal end 44, the two cutting elementsleeves 230 a,b preventing direct contact between the cutting elementengagement element 1170 and the cutting element portions 144 a, 144 b.

FIG. 16 is a side view of the device distal end 16 showing a slidablesupport ribbon 2160 wherein the sliding support ribbon distal end 164 isfixedly coupled to the inner member distal end 34, in accordance with anembodiment. When the inner member distal end 34 is exposed by thewithdrawing tube member distal end 24, the user may pull the slidingsupport ribbon proximal end 162 in the proximal direction so as to flexthe inner member distal end 34 into a desired curve to present thecutting element distal end 44 at an angle alpha to the tube member axisX. The user may control the sliding support ribbon distal end 164 in adesired position by pulling or pushing a snare 166 at the slidingsupport ribbon proximal end 162. It is appreciated that the slidablesupport ribbon 2160 may also be moved proximally and distally by theapparatus presented for the other embodiments herein or by apparatusknown in the art.

As previously discussed, the cutting element 40 is operable for cuttingand severing tissue. The cutting element 40 comprises a cutting elementproximal end 42 that engages the inner member 30 and a cutting elementdistal end 44, at least a portion of which is used to cut and severtissue.

Various embodiments of the cutting element proximal end 42 areanticipated. In general, embodiments of the cutting element proximal end42 are anticipated that either couple with the inner member distal end34 or pass through the inner member 30 to couple with other elementswithin the handle 50. It is appreciated that there are many couplingelements that may be used to provide fixed or removable coupling betweenthe inner member distal end 34 and the cutting element proximal end 42.

In accordance with an embodiment, a cutting element 40 is provided thatmay be removably coupled with the inner member distal end 34. FIG. 17 isa side cross-sectional view of an embodiment wherein the cutting elementproximal end 42 and the inner member distal end 34 are operable forremovable coupling engagement therebetween. The cutting element proximalend 42 comprises a mating element 37 and the inner member distal end 34comprises a receiving element 35. The mating element 37 and thereceiving element 35 are operable for removable coupling therebetween,wherein the mating element 37 is received and coupled to the receivingelement 35.

In accordance with an embodiment, a plurality of cutting elements 40 maybe provided, each suitable for a particular purpose such that onecutting element 40 may be interchanged on the inner member distal end 34with another cutting element 40 of a same or different configuration. Byway of example, cutting elements 40 of differing sizes and shapes may beprovided suitable for a particular purpose. Further, as the cuttingelement 40 becomes dull, a replacement cutting element 40 may replacethe first.

In accordance with other embodiments, a cutting element 40 is providedthat comprises a cutting element proximal end 42 that passes through theinner member 30 and is operable for coupling with elements within thehandle 50. FIG. 18 is a side, cut-away view of an inner member 30further comprising at least one inner member lumen 36 that extends fromthe inner member proximal end 32 to the inner member distal end 34therethrough. In accordance with the embodiment of FIG. 18, the cuttingelement 40 comprises an elongated member that forms a contiguous elementthat defines a loop 46 at the cutting element distal end 44 and two ends48 at the cutting element proximal end 42. In accordance with anembodiment, the cutting element 40 is a wire. In another embodiment, thecutting element 40 is a ribbon, that is, a flat-sided elongated memberthat defines a loop 46 at the cutting element distal end 44 with the twoends 48 of the ribbon forming the cutting element proximal end 42. Thecutting element proximal end 42 is operable to be received within theinner member lumen 36 and extend from the inner member proximal end 32suitable for a particular purpose discussed below.

Various embodiments of the cutting element distal end 44 areanticipated. In accordance with an embodiment, the cutting elementdistal end 44 comprises a blade that is operable for cutting andsevering tissue. In accordance with other embodiments, the cuttingelement distal end 44 comprises a loop 46, such as, but not limited to aloop of wire and ribbon. At least a portion of the cutting elementdistal end 44 comprises one or more sharp portions 45 that are suitablefor severing tissue. FIG. 18 shows an embodiment of a cutting elementdistal end 44, in accordance with an embodiment. The cutting elementdistal end 44 comprises a wire in the form of a loop 46 including asharp edge 45 that is preferentially sharp so as to cut tissue. Thesharp edge 45 is operable such that it may cut into adjacent tissue asit is released by the tube member distal end 24 and as the tissuesevering device 10 is pulled proximally toward the user.

FIG. 19A is a top view showing an embodiment of a cutting element 40 a,in accordance with an embodiment. The cutting element distal end 44comprises a ribbon in the form of a loop 46 including a sharp edge 45that is preferentially sharp so as to cut tissue. A broad surface 41 ofthe cutting element 40 a is generally parallel to a plane defined by theloop 46 so as to present the sharp edge 45 also generally parallel withthe plane defined by the loop 46.

FIG. 19B is a perspective view showing an embodiment of a cuttingelement 40 b, in accordance with an embodiment. The cutting elementdistal end 44 comprises a ribbon in the form of a loop 46 including asharp edge 45 that is preferentially sharp so as to cut tissue, and adull edge 47 that is not sharp relative to the sharp edge 45, such thatit may not cut tissue. A broad surface 41 of the cutting element 40 b isgenerally perpendicular to a plane defined by the loop 46 so as topresent the sharp edge 45 also generally perpendicular with the planedefined by the loop 46.

The sharp edge 45 is operable to cut into adjacent tissue as it isreleased by the tube member distal end 24, as shown in FIG. 11B, and asthe tissue severing device 10 is pulled proximally toward the user. Thesharp edge 45 is presented on the edge of the cutting element distal end44 that faces proximally when it is released by the tube member distalend 24. In other embodiments, the sharp edge 45 may comprise serrationsso as to assist in severing tissue.

Various sizes and configurations of embodiments of the cutting elementdistal end 44 are anticipated. In the embodiment of FIG. 3, the cuttingelement distal end 44 is operable to fit within the tube member lumen 26without elastic deformation of the cutting element distal end 44.

In the embodiment of FIGS. 5A-5B, the cutting element distal end 44comprises a substantially elastic material such that the loop 46 mayhave a diameter somewhat larger than the inner diameter of the tubemember lumen 26. When the tube member distal end 24 is advanced in thedistal direction, the cutting element distal end 44 is operable tosubstantially elastically deform and be slidingly received within thetube member lumen 26 as shown in FIG. 5A. When the tube member distalend 24 is advanced in the proximal direction, the cutting element distalend 44 is operable to exit the tube member lumen 26 and substantiallyelastically expand therefrom. In accordance with an embodiment, thecutting element distal end 44 is in the form of a substantially ovalloop 46 when released from the tube member lumen 26. The loop 46 isoperable to be biased to open up when the tube member distal end 24 iswithdrawn therefrom. When the tube member 20 is advanced over thecutting element distal end 44, the cutting element distal end 44 isoperable to elastically deform under the impinging force of the tubemember distal end 24 into a substantially closed or pinched-down ovalshape so as to enter the tube member lumen 26. In accordance with anembodiment, and by way of example and not limited thereto, the loop 46of the cutting element distal end 44 may have a diameter of about 12 mm,wherein the tube member may have an inner diameter of about 5 mm.

It is appreciated that the cutting element 40 may be constructed frommany typed of materials, such as, but not limited to, stainless steeland shape-memory metals or metal alloys such as, but not limited to,nickel-titanium alloy.

In accordance with an embodiment, the cutting element distal end 44 issubstantially uniformly elastically deformable. In accordance with otherembodiments, the cutting element distal end 44 comprises one or moreelastic regions operable to provide elastic deformation of the cuttingelement distal end 44.

In accordance with an embodiment, the cutting element distal end 44 isformed as a single element. In accordance with another embodiment, thecutting element distal end 44 may be formed by integrating or joiningseparate components comprising one or more materials, at least some ofwhich have elastic properties. FIGS. 19C and 19D are top views showingan embodiment of a cutting element 40 c, in accordance with anembodiment. The cutting element distal end 44 comprises a ribbon in theform of a loop 46 comprising two stainless steel portions 141 coupledtogether by a super-elastic nickel-titanium alloy portion 241, whereinthe nickel-titanium portion 241 provides a significant portion of theelasticity of the cutting element distal end 44 to a collapsed shape asshown in FIG. 19C and the stainless steel portions 141 providinggenerally the bias to the expanded shape as shown in FIG. 19D.

It is also appreciated that the cutting element 40 may be constructedwith geometric features that assist in forming a loop at the cuttingelement distal end 44. FIG. 19E is a top view showing an embodiment of acutting element 40 e, in accordance with an embodiment. The cuttingelement distal end 44 comprises a ribbon defining a crease 341 acrossthe width of the ribbon. The crease 341 is operable to allow forpreferential bending to assist in compressing the cutting element distalend 44 into an elongated loop for the cutting element distal end 44 tobe received within the tube member lumen 26.

FIG. 19F is a top view showing another embodiment of a cutting element40 f, in accordance with an embodiment. The cutting element distal end44 comprises a ribbon defining a necked-down portion 441. Thenecked-down portion 441 is operable to allow for preferential bending toassist in compressing the cutting element distal end 44 into anelongated loop for the cutting element distal end 44 to be receivedwithin the tube member lumen 26.

FIG. 20 is a side partial cut-away view of the device distal end 16wherein the cutting element distal end 44 has a bias to an angle beta tothe tube member axis X, in accordance with an embodiment. The bias ofthe cutting element distal end 44 is operable such that the sharp edge45 is presented to tissue when the device distal end 16 is placed alongside and adjacent to tissue to be severed as will be discussed below. Inaccordance with this embodiment, the tissue may begin to be severedprior to the emergence of the inner member distal end 34 from the tubemember distal end 24.

In accordance with an embodiment, the inner member 30 and thus thecutting element 40 may be operable to be assembled in the tube memberlumen 36 such that the cutting element distal end 44 may be retained atone or more predetermined angles with respect to the handle 50. By wayof example, in accordance with an embodiment, the cutting element distalend 44 may be operable to be assembled to extend from the tube memberdistal end 24 at one of four directions, such as up, right, down, orleft, as viewed along the tube member axis X from the handle 50.

In accordance with embodiments of the tissue cutting device 10, anenergy source is provided to assist the cutting element proximal end 44in cutting and severing tissue. FIG. 21 is a side partial cut-away viewof a tissue severing device 10 comprising an energy source 90, inaccordance with an embodiment. The cutting element proximal end 42comprises two ends 48, such as shown in the embodiment of FIG. 18. Thecutting element proximal end 42 extends through the inner member lumen36 to the handle 50. Within the handle 50, the two ends 48 of thecutting element proximal end 42 are coupled to the energy source 90operable to assist in severing tissue. It is appreciated that the energysource 90 may employ one or more energy modes that are operable toassist in cutting and severing tissue, such as, but not limited to,mechanical, radio frequency, thermal, ultrasonic, and any other suitableenergy.

In accordance with an embodiment, the energy source 90 is a radiofrequency energy source 90, and the cutting element 40 may function as acomponent of a monopolar or a bipolar system. The radio frequency energysource 90 may be operable as an electrocautery instrument so as toprovide, among other things, coagulation of small bleeding vessels thatmay be encountered during the severing process.

In accordance with another embodiment, the two ends 48 of the cuttingelement proximal end 42 are coupled to an energy source 90 that ismechanical in operation. In accordance with an embodiment, the energysource 90 is an ultrasonic source that is operable to impart a vibratoryaction to the cutting element distal end 44 to assist in severing thetissue. In another embodiment, the energy source 90 is a mechanicaloscillator that is operable to rapidly and alternatively pull on the twoends 48 of the cutting element proximal end 42 so as to impart a sawingmotion to the cutting element distal end 44 to assist in severing thetissue.

In another embodiment, the energy source 90 is a mechanical oscillator,such as, but not limited to, a motor, that is operable to rapidly andalternatively push-pull on the two ends 48 of the cutting elementproximal end 42 so as to provide a rapid in and out movement of thecutting element distal end 44 to assist in severing tissue. Inaccordance with another embodiment, the inner member lumen 36 comprisesa track that is operable to guide the movement of the cutting elementdistal end 44 which is coupled to a trolley that is adapted to couplewith the track.

In yet another embodiment, the energy source 90 is a thermal source thatis operable to heat the cutting element distal end 44 to assist insevering the tissue.

In accordance with embodiments wherein the cutting element proximal end42 couples with the inner member distal end 34, the cutting elementdistal end 44 may be energized with energy by coupling the energy source90 to the inner member proximal end 32. The energy from the energysource 90 is communicated to the cutting element distal end 44 via theinner member 30. It is appreciated that many energy sources may be usedto communicate energy to the cutting element distal end 44 via the innermember 30. It is also appreciated that a mechanical energy source may beparticularly effective. In accordance with an embodiment, the innermember proximal end 32 is coupled to a mechanical oscillator that isoperable to rapidly push-pull on the inner member proximal end 32 so asto impart motion to the cutting element distal end 44 to assist insevering the tissue. In accordance with an embodiment, the energy source90 is an ultrasonic source that is operable to impart a vibratory actionto the inner member 30 that is communicated to the cutting elementdistal end 44 to assist in severing tissue.

In accordance with and embodiment, by way of example, the energy source90 is a variable speed drive operable to induce oscillatory motion tothe cutting element distal end 44 either directly or via the innermember 30. Referring again to FIG. 21, the drive includes a motor 92, atransmission 93, and a switch 94. The switch 94 comprises a firstcontact 95 housed in the handle 50 adjacent a button contact 96.

When the button contact 96 is in an initial position, the switch 94represents an open electrical circuit. Thus, no current is supplied tothe motor 92, and the cutting element distal end 44 is stationary. Themotor 92 is electrically connected to power via the switch 94 and acontrol 99 when the button contact 96 is in the inward most position soas to make electric coupling with the first contact 95, as will bedescribed more fully hereafter.

The control 99 includes a rotary pot 97 operable to allow a user tocontrol the power available to the motor 92 and, thus, the speed of thecutting element distal end 44. Appropriate lengths of electricalconductors 91 electrically interconnect the control 99, the switch, 94,and the motor 92.

The button contact 96 nests within a track (not shown) defined by thehandle 50. A button return spring (not shown), which may be mountedbetween the button contact 96 and a portion of the handle 50, biases thebutton contact 96 in an outward position away from the first contact 95and out of electrical communication therewith. The transmission 93 isoperable to convert rotational motion from the motor 92 to anoscillatory motion that is communicated to the cutting element distalend 44 by coupling the transmission 93 to either the cutting elementproximal end 42 or the inner member proximal end 32.

In accordance with embodiments of the tissue cutting device 10, andreferring to FIGS. 1A and 1B, the tissue cutting device 10 furthercomprises an engagement means 70 being operable for moving the tubemember 20 proximally and distally over the inner member 30. It isanticipated that there are many engagement means 70 that may be used toprovide the function for moving the tube member 20 proximally anddistally, including unpowered, powered, manual and automatic means, someof which will be described further below. In accordance with anembodiment, wherein the handle 50 comprises the engagement means 70 as aslidable engagement element, and the tube member 20 is operable to bemoved proximally and distally over the inner member 30 by a usergrasping the tube member 20 and sliding the tube member 20 through theslidable engagement element within the handle 50.

The tissue severing device 10, shown in FIGS. 1 and 21, furthercomprises an engagement means 70 in the form of a tube member movingelement 170 operable to engage the tube member proximal end 22 formoving the tube member 20 proximally and distally over the inner member30. In accordance with an embodiment as shown in FIG. 21, the tubemember moving element 170 that is operable for axially moving the tubemember 20 includes a rack 56 and pinion 57. It is understood that thereare many rack and pinion configurations in the art suitable for aparticular purpose. For example, but not limited thereto, in accordancewith an embodiment, the rack 56 comprises a plurality of spaced notchesor grooves located at the tube member proximal end 22. The rack 56 maybe an integral feature of the tube member 20 or an element that iscoupled to the tube member proximal end 22. The pinion 57 comprises anengagement wheel having teeth that operably engage the spaced notches ofthe rack 56. In operation, when the pinion 57 is rotated in a clockwisedirection, the rack 56 is engaged to advance the tube member 20 axiallyin a proximal direction. When the pinion 57 is rotated in the oppositedirection, the rack 56 is engaged to move the tube member 20 axially ina distal direction.

A tube member moving element 170 for axially moving the tube member 20relative to the inner member 30 and cutting element 40 may be providedby many known means, such as, but not limited to a rack and pinion drivesystem wherein the pinion comprises helical threads and is operable byrotating the pinion along the tube member axis X, such as shown in theembodiment of FIGS. 1A and 1B. Other linear actuators may also be used,suitable for a particular purpose. It is appreciated that the tubemember moving element 170 may be electrically and manually operated.

It is appreciated that the tube member moving element 170 for axiallymoving the tube member 20 relative to the inner member 30 and cuttingelement 40 may be operably coupled to the energy source 90 forenergizing the cutting element distal end 44. By way of example, but notlimited thereto, in accordance with an embodiment, the energy source 90for energizing the cutting element distal end 44 is activated only whenthe tube member 20 has been moved proximally by a predetermined amount.Such a configuration may prevent the activation of the energy source 90prior to the withdrawal of the cutting element distal end 44 from thecutting element distal end 44.

It is appreciated that other elements may be incorporated into thetissue severing device 10. By way of example, but not limited thereto,the tube member 20 may include one or more accessory lumens such as, butnot limited to, for suction, irrigation, inflation. Gas, liquid, or acombination thereof from an external source may be administered througha communications lumen 225, shown in FIG. 21, and coupled to the tubemember lumen 26 at the tube member proximal end 22. For example, but notlimited thereto, an aqueous solution may be employed for irrigationpurposes or a local anesthetic, such as lidocaine, may be administeredthrough the tube member lumen 26 so as to exit the tube member distalend 24. In addition, the tube member lumen 26 may be operativelyconnected to an external vacuum source. The external vacuum source mayprovide suction to, for example, but not limited to, remove from thepatient, fluids, such as, but not limited to, blood, irrigation fluid orsmoke generated during use of the cutting element 40 or other device.

In using the tissue severing device 10 of an embodiment shown in FIG.21, the cutting element 40 and inner member 30 are first containedwithin the tube member lumen 26 of the tube member 20. The tube memberdistal end 24 may be passed through a trocar sleeve that has been placedwithin a patient and placed along side and adjacent to tissue 80 to besevered as shown in FIG. 22. FIG. 22 is a side view of the device distalend 16 placed along side tissue 80 to be severed. The tube member 20 ismoved axially proximally so as to withdraw from and expose the cuttingelement distal end 44 and the inner member distal end 34. The cuttingelement distal end 44 is operable to impinge and cut into the adjacenttissue 80 substantially laterally or laterally and proximally (towardthe handle 50) so as to create an arc-shaped cut 86 into the tissue 80,as shown in FIG. 22. Once the cutting element 40 is exposed the desiredamount, the handle 50, as shown in FIG. 1B, is pulled proximally so asto pull the extended cutting element distal end 44 through the tissue80, severing the tissue 80, with the severed tissue 85 extruding throughthe loop 46 of the cutting element distal end 44, as shown in FIG. 23.

The support ribbon 60 substantially prevents the inner shaft distal end34 from extending distally toward the tube member axis X during thecutting operation as well as prevents the cutting element distal end 44from cutting too deeply. The support ribbon 60 guides the tissue 80 intothe loop 46 of the cutting element distal end 44 and therefore limitsthe depth of the cut 86. Were the cutting element distal end 44 to cuttoo deeply, the cutting element distal end 44 may get stuck during thecutting operation. Severed tissue 85 may be removed from the patient byanother device.

Additional severing operations may be performed by moving the exposedcutting element distal end 44 to another portion of tissue 80 to besevered and impinging the cutting element distal end 44 into the tissue80. Alternatively, after each cutting operation, the tube member 20 maythereafter be moved distally so as to advance over the inner memberdistal end 34 and the cutting element distal end 44. The tube memberdistal end 24 is again placed along side tissue 80 to be severed and theprocess is repeated.

It is appreciated that the angle of the cutting element distal end 44 tothe tissue 80 may be changed by the selective positioning of the tubemember distal end 24 with respect to the cutting element distal end 44or the inner member distal end 34. The user may adjust the angle of thecutting element distal end 44 at any time during the cutting operationso as to control the cutting operation. By way of example, but notlimited thereto, less tissue 80 may be severed by reducing the exposureof the cutting element distal end 44. By way of another non-limitingexample, the initiation of the cutting operation may be done at first bylimiting the exposure of the cutting element distal end 44 andsubsequently increasing the exposure of the cutting element distal end44 as the tissue severing device 10 is pulled proximally during thecutting operation.

It is appreciated that by virtue of the cutting element distal end 44being operable to impinge and cut into the adjacent tissue 80substantially laterally or combination laterally and proximally (towardthe handle 50) so as to create an arc-shaped cut 86 into the tissue 80,the cutting element distal end 44 may be placed and the cut initiatedcloser to vital organs and tissue that is to remain unsevered. Inembodiments of the tissue severing device 10 disclosed herein, theuterus may be morcellated while the uterus is still attached to thecervix. The lateral cutting action of the embodiments of the tissuesevering device 10 greatly reduce the risk of injuring adjacent tissueand organs as compared with uterus amputation procedures, particularlyfor those embodiments of the tissue severing device 10 that do notincorporate heat in the cutting operation. Further, since no amputationof the uterus prior to morcellation is required, only one device, thetissue severing device 10, is required for both the separation of theuterus from the cervix and morcellating the uterus for removal, reducingthe cost and complexity of the surgery. It is evident that embodimentsof the tissue severing device 10 disclosed herein presents a significantimprovement over prior art devices, as, among other things, downward(distal) traction is not employed and uterus amputation and thecorresponding amputation surgical device is not required.

It may be necessary for the surgeon to rest the device distal end 16 inthe patient while other operations are performed. The tube member 20 maybe moved distally so as to advance over the inner member distal end 34and the cutting element distal end 44 so as to prevent the cuttingelement distal end 44 from injuring the patient while resting in thepatient.

In accordance with another method of using the tissue severing device10, the tube member distal end 24 is moved proximately so as to withdrawfrom the cutting element distal end 44 and the inner member distal end34. The cutting element distal end 44 is placed beyond a leading edge 82of the tissue 80 with the sharp portion 45 of the cutting element distalend 44 placed adjacent tissue 80 to be severed, as shown in FIG. 24.Cutting of the tissue 80 is affected by pulling proximally on the tissuesevering device.

Referring again to the ability of the inner member distal end 34 todeform or flex from a substantially straight configuration to a curvedor angled configuration, it is appreciated that articulation apparatusoperable to allow for articulation of the inner member distal end 34 maybe provided by many apparatus, such as, but not limited to, nested ringsections, sliding corrugated sections, pivots, movable joints, andextensible tubing, such as, but not limited to, bellows-type tubing. Itis also appreciated that means for providing control of, movement of,and/or a bias to the segments into a predetermined configuration, suchas substantially straight or to form a curve of a predetermined angle,may be provided by many apparatus, such as, but not limited to, elasticelements, such as, but not limited to, springs and spine members, andmechanical elements, such as, but not limited to, a slidable supportribbon 165 and pull-wires and rods.

FIG. 25 is a perspective view of a device distal end 16 including aninner member distal end 34 that is operable to allow for articulation,in accordance with an embodiment. At least a portion of the inner memberdistal end 34 comprises two or more segments 34 a, 34 b that areinterconnected by a bellows joint 37 supported by one or more spinemembers 39. The one or more spine members 39 may be operable to providea predetermined bias on the segments 34 a, 34 b, so as to present theinner member distal end 34 in a straight or curved configurationsuitable for a particular purposes.

FIG. 26 is a perspective view of a device distal end 16 includinganother inner member distal end 34 that is operable to allow forarticulation, in accordance with an embodiment. At least a portion ofthe inner member distal end 34 comprises two or more segments 34 a, 34 bthat are interconnected by a pivot joint 37. The movement of the pivotjoint 37 may be controlled, at least in part, by the engagement of theslidable support ribbon 165 with the engagement ring 168 so as topresent the inner member distal end 34 in a straight or curvedconfiguration. The pivot joint 37 is located between the inner memberproximal end 32 and the engagement ring 168.

It is appreciated that the tube member distal end 24 may have a tubeflare portion 29 to guide the engagement of the slidable support ribbon165 and/or the inner member distal end 34 as shown in FIG. 25. The tubeflare portion 29 is operable to provide a smooth bend radius for thecomponents that may engage it.

In operation, when the tube member distal end 24 is advanced over thecutting element distal end 44, the slidable support ribbon 165 and theinner member distal end 34 lie substantially parallel with each otherwithin the tube member distal end 24. As the tube member distal end 24is withdrawn, the cutting element distal end 44 expands into an openposition. As the tube member distal end 24 is further withdrawn, thecutting element engagement element 1170 engages the cutting elementportions 144 a, 144 b of the cutting element distal end 44 to stabilize,or hold-open, the cutting element distal end 44 during subsequent tissuesevering. The flared portion 167 of the slidable support ribbon distalend 164 engages the engagement ring 168 reducing any further traction onthe cutting element distal end 44 by the cutting element engagementelement 1170. The crease 1141 preferentially bends so as to reduceengagement of the slidable support ribbon distal end 164 on the tubemember distal end 24.

While the invention has been described in connection with specificembodiments thereof, it will be understood that it is capable of furthermodification, and this application is intended to cover any variations,uses, or adaptations of the invention following, in general, theprinciples of the invention and including such departures from thepresent disclosure as come within known or customary practice in the artto which the invention pertains and as may be applied to the essentialfeatures hereinbefore set forth, and as fall within the scope of theinvention and the limits of the appended claims.

1-27. (canceled)
 28. A tissue severing device comprising: a handle; atube member including an elongated tube having a tube member proximalend extending into the handle and a tube member distal end opposite thetube member proximal end, the tube member defining a tube member lumenthat extends through the tube member proximal end to the tube memberdistal end and defining a tube member axis; an inner member including anelongated body having an inner member proximal end extending through thetube member lumen and into the handle and an inner member distal endopposite the inner member proximal end, the inner member being operableto be received within the tube member lumen; a cutting element includinga cutting element proximal end and a cutting element distal end oppositethe cutting element proximal end, the cutting element proximal endextending into the inner member distal end, the cutting element distalend extending from the inner member distal end, the tube member distalend being operable to move distally over and receive the inner memberdistal end and the inner member distal end therein, and the tube memberdistal end being operable to move in a proximal direction to expose thecutting element distal end; and a slidable support ribbon operable forsupporting the inner member distal end in a curved position when theinner member distal end is at least partially exposed by the withdrawalof the tube member distal end, the slidable support ribbon comprising anelongated body including a slidable support ribbon proximal end and aslidable support ribbon distal end opposite the slidable support ribbonproximal end, the slidable support ribbon proximal end extending throughthe tube member lumen from about the tube member proximal end to aboutthe tube member distal end and adjacent the inner member, the slidablesupport ribbon distal end positioned adjacent the inner member distalend and the cutting element distal end.
 29. The tissue severing deviceof claim 28, wherein the slidable support ribbon proximal end ispositioned generally adjacent the handle and may be operably engaged bya user.
 30. The tissue severing device of claim 28, wherein the slidablesupport ribbon distal end is operable to support the inner member distalend into a curved shape when the tube member distal end is withdrawntherefrom, the slidable support ribbon being operable to substantiallyprevent the inner member distal end from extending toward the tubemember axis when the cutting element distal end is pulled through tissueto be severed. 31-35. (canceled)
 36. The tissue severing device of claim30, wherein the slidable support ribbon distal end is operably coupledto the tube member so as to begin withdrawing proximally from beingadjacent the cutting element distal end as the cutting element distalend begins to be exposed by the withdrawing tube member distal end, theslidable support ribbon distal end operable to be exposed substantiallyconcurrently with the exposure of the inner member distal end by thetube member distal end.
 37. (canceled)
 38. The tissue severing device ofclaim 30, wherein the tube member distal end is operable to be withdrawnso as to expose a portion of the inner member distal end, the slidablesupport ribbon distal end is operable to be withdrawn from adjacent thecutting element distal end and operably engage the inner member distalend so as to support the inner member distal end into an angle to thetube member axis.
 39. The tissue severing device of claim 30, whereinthe slidable support ribbon distal end is slidingly coupled to the innermember distal end, wherein when the inner member distal end is exposedby withdrawing the tube member distal end, a user may pull the slidablesupport ribbon proximal end in the proximal direction so as to withdrawthe slidable support ribbon distal end from adjacent the cutting elementdistal end and flex the inner member distal end into a desired angle tothe tube member axis.
 40. The tissue severing device of claim 30,further comprising an engagement ring coupled to the inner member distalend, the slidable support ribbon distal end and the inner member distalend are slidingly coupled by cooperative engagement of the inner memberdistal end and the engagement ring, the slidable support ribbon distalend comprising a substantially uniform width body portion and a flaredportion at about the inner member distal end, wherein the flared portionhas a width that is larger than the body portion, the engagement ringcomprising a shape of a partial loop coupled to the inner member distalend transverse to an inner member axis, the engagement ring beingoperable to slidingly receive the body portion of the slidable supportribbon distal end and is undersized so as to not be able to receive theflared portion therethrough, the flared portion operable as a catch suchthat there is no further axial movement of the slidable support ribbondistal end relative to the engagement ring when the flared portionengages the engagement ring, wherein the engagement of the flare portionwith the engagement ring is operable to provide a means for pulling theinner member distal end proximally and thus flex the inner member distalend to present the cutting element distal end to an angle to the tubemember axis, wherein the engagement ring being operable to be slidinglyreceived within the tube member lumen. 41-42. (canceled)
 43. The tissuesevering device of claim 40, wherein the slidable support ribbon distalend further comprises a cutting element engagement element operable toengage the cutting element distal end about the inner member distal end,operable to open and stabilize the cutting element distal end when thecutting element engagement element engages the cutting element distalend about the about the inner member distal end. 44-46. (canceled) 47.The tissue severing device of claim 28, wherein the slidable supportribbon proximal end is cooperatively engaged with the tube memberproximal end such that when the tube member proximal end is movedaxially, the slidable support ribbon is operable to be moved axially aswell.
 48. The tissue severing device of claim 28, wherein the slidablesupport ribbon proximal end further comprising a snare extending at anangle from the slidable support ribbon proximal end operable to engagethe tube member proximal end such that when the tube member proximal endis moved axially, the slidable support ribbon is operable to be movedaxially.
 49. The tissue severing device of claim 43, wherein the cuttingelement engagement element is a flange extending at an acute angle fromthe slidable support ribbon distal end and extending into the loopformed by the cutting element distal end when adjacent thereto. 50.(canceled)
 51. The tissue severing device of claim 28, wherein thecutting element comprises a cutting element proximal end and a cuttingelement distal end opposite the cutting element proximal end, thecutting element proximal end and the inner member distal end removablycoupled therebetween, the cutting element distal end including at leasta portion operable to cut and sever tissue.
 52. (canceled)
 53. Thetissue severing device of claim 28, wherein the cutting element distalend defines a loop, at least a portion of the cutting element distal endincluding one or more sharp portions that are suitable for severingtissue.
 54. The tissue severing device of claim 53, wherein the loop isoperable to be biased to expand when the tube member distal end iswithdrawn therefrom, and wherein the cutting element distal end beingelastically deformed under the impinging force of the tube member distalend so as to enter and be contained by the tube member lumen when thetube member is advanced over the cutting element distal end. 55.(canceled)
 56. The tissue severing device of claim 28, wherein the innermember further comprises at least one inner member lumen extendingthrough the inner member proximal end and the inner member distal end,the cutting element proximal end extending through the inner memberlumen and coupled within the handle.
 57. The tissue severing device ofclaim 56, wherein the cutting element comprises a ribbon defining aflat-sided elongated member that defines a loop at the cutting elementdistal end and two ends forming the cutting element proximal end, thecutting element proximal end received within the inner member lumen andextending from the inner member proximal end.
 58. The tissue severingdevice of claim 28, wherein the cutting element distal end has a bias toform an angle to the tube member axis.
 59. The tissue severing device ofclaim 28, further comprising an energy source coupled to the cuttingelement and operable to assist the cutting element proximal end incutting and severing tissue. 60-63. (canceled)
 64. The tissue severingdevice of claim 59, wherein the energy source is a mechanical oscillatorthat is operable to rapidly and alternatively pull on the two ends ofthe cutting element proximal end so as to impart a sawing motion to thecutting element distal end. 65-66. (canceled)
 67. The tissue severingdevice of claim 28, wherein the inner member proximal end is coupled toa mechanical oscillator that is operable to rapidly push-pull on theinner member proximal end so as to impart motion to the cutting elementdistal end. 68-118. (canceled)